Remove outdated comparison

Author: gaearon

content/docs/faq-styling.md

@@ -42,7 +42,7 @@ CSS classes are generally better for performance than inline styles.
 
 ### What is CSS-in-JS? {#what-is-css-in-js}
 
-"CSS-in-JS" refers to a pattern where CSS is composed using JavaScript instead of defined in external files. Read a comparison of CSS-in-JS libraries [here](https://github.com/MicheleBertoli/css-in-js).
+"CSS-in-JS" refers to a pattern where CSS is composed using JavaScript instead of defined in external files.
 
 _Note that this functionality is not a part of React, but provided by third-party libraries._ React does not have an opinion about how styles are defined; if in doubt, a good starting point is to define your styles in a separate `*.css` file as usual and refer to them using [`className`](/docs/dom-elements.html#classname).